The present invention relates generally to the field of container formation. The present invention relates specifically to a method and apparatus for blow molding a squeezable container from an injection molded preform.
Squeezable tubular containers are used to hold a wide variety of products including household consumer products, food products, industrial products, medical products, etc. Typically, squeezable tubular containers are used to hold a material (e.g., a liquid, a gel, a paste, etc.) which has a consistency such that the material may be dispensed through a dispensing opening provided on the tubular container by squeezing the sides of the tubular container. Some materials or products that may be held in a squeezable tubular container include toothpaste, lotions, gels, glue, edible materials (e.g., squeezable cheese, tomato paste, etc.), cleaning products, pharmaceutical creams, etc.
Squeezable tubular containers are typically manufactured from an extruded plastic tube having a separate threaded head component that includes a dispensing opening. To make the complete container, an extruded tube of the desired length is produced, and the separate head component is attached or coupled to one end of the tube. The separate head component of such squeezable tubes are typically attached to the extruded plastic tube by welding or an adhesive that requires a separate step in the manufacturing process. Following attachment of the head component, the end of the tube opposite of the head component remains open. The tube is filled with the desired material, and the open end of the tube is sealed by crimping together the material of the open end.
Thus, an extruded tube manufactured via this process typically has a circular cross-section at the end that is attached to the head component and the opposite, crimped end is flat. Because a cylindrical tube (i.e., a tube having a constant diameter along its length) is used to make the tubular container during this process, the length of the crimped, flat end typically is about half of the circumference of the round end of the tube body adjacent the head component. Further, making tubes using the extrusion-based process may generate significant waste or scrap material due to the starting and stopping of the extrusion machinery or other machinery at various stages of the process. In addition, the extrusion-based process involves an additional step to attach the separate head component to the tubular container body.